1 Processor/IO Bound Programs

If run by itself, an I/O bound program spends more time waiting for I/O than using the processor and vice versa for the processor-bound. Given a short-term scheduling algorithm favoring those programs that have used little processor time in the recent past. Explain why this algorithm favors I/O bound programs and yet does not permanently deny processor time to processor bound programs.

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Characteristics of a Short-term Scheduling algorithm are

1. First-Come, First-Served (FCFS, or FIFO)
2. As process becomes ready, join Ready queue, scheduler
3. Always selects process that has been in queue longest
4. Better for long processes than short ones
5. Favors CPU-bound over I/O-bound processes
6. Needs priorities, on uniprocessor, to make it effective

As you can see from the above points, if a I/O bound ...

Solution Summary

If run by itself, an I/O bound program spends more time waiting for I/O than using the processor and vice versa for the processor-bound. Given a short-term scheduling algorithm favoring those programs that have used little processor time in the recent past. Explain why this algorithm favors I/O bound programs and yet does not permanently deny processor time to processor bound programs.